Unless you ran over your kids bike and the bells jammed in there...NO! Disconnect the driveshaft from the t-case (and not the diff) and spin it, if it makes noise it's in the frontend (diff, axles, hubs, etc) try it with and w/o the hubs locked. Then turn the t-case end in the different ranges. If its quiet on both sides, it's probably the driveshaft. It will take some time, but process of elimination is what it will probably boil down to. Let us know what you find.

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